I remember when I first watched Sister Wendy's TV series, I was totally amazed at her knowledge of art and more so at her appreciation for it.
She has a very relaxing manner and a confidence that is reassuringly humble in a way.
If you have not seen Sister Wendy before and you would like to learn about 'art', then she is the one to do it!
There are a number of videos on You Tube and I am sure PBS may have copies of her series for sale.
I could listen to and learn from her for hours........